Production managing system of semiconductor device

ABSTRACT

A production managing system for semiconductor devices includes, in a semiconductor producing center C, production devices  11   a - 11   c  for producing semiconductor devices, in-line measuring devices  12   a - 12   c  for measuring data of a lot, a database  2  storing data of production methods, the measured data, the specifications of the process steps corresponding to the measured data, the estimated yield, the data of lot input date and hour, the data of the scheduled date on which the process step is performed, the data of actual date of completion in every step and the data of the scheduled date of completion of the semiconductor devices of every lot, correspondingly to a lot number data of the semiconductor devices (chips) and a server  1  including an estimated yield operating unit la for calculating the estimated yield, which is a final yield, on the basis of the specifications and the measured data, and a production managing unit  1   b  for performing a production management of semiconductor devices ordered by a user on the basis of the respective data inputted by the user and the estimated yield, wherein a user terminal of the user not only performs a determination whether or not the process processing in every process is normal but also estimates the final number of normal products ordered by the user and obtainable finally.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a production managing system ofsemiconductor devices in which a production of semiconductor devices ismanaged by a remote user by using an information communication line suchas an internet, etc.

[0003] 2. Description of Related Art

[0004] The production management of semiconductor devices ordered by auser has been performed by a semiconductor device manufacturer bymeasuring parameters of the semiconductor devices in respectiveproduction process steps thereof along a production line and checkingthe measured parameters on whether or not the parameters are withinpredetermined specifications.

[0005] That is, for example, thickness of a thin film formed on asubstrate is checked on whether or not its thickness is within athickness specification thereof in the forming step of the thin film anda wiring pattern is checked on whether or not a width thereof is withina width specification of the wiring pattern in a wiring pattern formingstep in which the wiring pattern is formed by etching the thin filmthrough a photolithographic step.

[0006] However, a production management in these checks is to merelydetermine whether or not a result of check is acceptable.

[0007] Final yield of semiconductor device, that is, the number ofsemiconductor devices obtained finally as acceptable products, isconfirmed by confirming electrical characteristics and operations ofcompleted semiconductor devices, which are functionally acceptable, byusing a semiconductor tester.

[0008] Therefore, it is usual that a user who ordered the semiconductordevices can not know the number of normal semiconductor devices, whichare practically obtained, before the production of all of them iscompleted.

[0009] As mentioned above, since, in the conventional productionmanagement of semiconductor devices, it is impossible for the user toknow the number of finally obtainable normal semiconductor devices inevery process and to confirm the number of normal semiconductor deviceshaving acceptable electric characteristics before the semiconductordevices are completed, the user can not know the number of normalproducts until the semiconductor devices are delivered to the user.

[0010] Therefore, if a result obtained in the check in every process cannot be detected by usual check in the conventional productionmanagement, there may be a case where the number of completed productsdelivered to the user is smaller than the number of products ordered bythe user.

[0011] Therefore, when the shortage of the number of normal products isconfirmed after the number of normal products is confirmed, it isnecessary for the user to throw in a lot (constituted with in unit ofwafer or wafers) again for production of semiconductor devices thenumber of which corresponds to the shortage. However, the production ofsemiconductor devices of the newly thrown lot usually takes about twomonths from the throwing-in of the lot to a completion of thesemiconductor devices. Therefore, in the case where the number of normalproducts is short due to abnormality of process, a production schedulethereof is delayed substantially.

SUMMARY OF THE INVENTION

[0012] The present invention was made under the circumstances and has anobject to provide a production managing system of semiconductor devices,which is capable of estimating not only the quality of processing inevery process step but also the number of finally obtainable normalsemiconductor devices ordered by a user in every process step such ascontact-hole forming step.

[0013] The production managing system according to the present inventionis featured by comprising, in a semiconductor device producing centerconnected to at least one usr terminal through an informationcommunication line, a plurality of production devices for performingproduction processes in respective process steps, a corresponding numberof in-line measuring devices provided next to the respective productiondevices, for measuring process parameters corresponding to therespective process steps of the production devices and outputtingresults of the measurements in units of lot of semiconductor devices asmeasured data, a database storing, for each wafer group including one ormore wafers, data of production method for producing semiconductordevices, the measured data, specifications of the process stepscorresponding to the measured data, estimated yields, data of the dateand hour of an input of the lot, data of the scheduled date on whicheach process step is performed, data of actual date of completion ofevery step and data of the scheduled date of completion of thesemiconductor devices, correspondingly to lot number data of thesemiconductor devices and a server including an estimated yieldoperating unit for calculating the estimated yield, which is a finalyield, on the basis of the specifications and the measured data, and aproduction managing unit for performing a production management ofsemiconductor devices ordered by a user on the basis of the respectivedata inputted by the user and the estimated yields, wherein the serverperforms write and read of the respective data inputted from the userterminal with respect to the database.

[0014] In this production managing system, the production managing unitmanages the production of semiconductor devices by producing processcontrol tables for the respective wafer groups, each of which iscomposed of the data of scheduled date and hour of each of the processsteps used for the lot management, on the basis of the production methoddata, the data of lot input date and hour and the data of scheduled dateof completion and controlling the process steps of the respective lotson the basis of the process control tables.

[0015] In this production managing system, the estimated yield operatingunit calculates the estimated final yield after the process steps of thelot is completed and the process parameters are measured on the basis ofthe specifications, on the basis of statistical values of the measureddata, the specifications and old data.

[0016] In this production managing system, the user terminal outputs thespecifications inputted by the user for respective process steps, dataof measuring positions indicative of positions on the wafer to bemeasured and element data indicative of the kind of elements to bemeasured to the server together with the lot number and the serverwrites the inputted specifications, the measuring position data and theelement data, in regions of the semiconductor devices corresponding tothe lot number data in the database.

[0017] In this production managing system, the user terminal outputsdata of re-input date and re-inputted wafer number inputted by the usercorrespondingly to the estimated yield to the server and the serverwrites the scheduled process data for every step of the lot having thewafers corresponding to the re-inputted wafer number data,correspondingly to the production schedule based on the re-input datedata and the re-inputted wafer number data.

[0018] In this production managing system, when the estimated yieldestimated by the measurement result in every step is lower than aminimum yield assigned by the user, the production managing unitnotifies the user terminal of the detection result.

[0019] In this production managing system, the in-line measuring devicesirradiate through-holes, which are formed in an insulating film forelectrical connection between wiring patterns laminated on both sides ofthe insulating film, with electron beam, measures electric currentvalues flowing correspondingly to configurations of the through-holesand outputs the measured current values as the measured data.

[0020] In this production managing system, the estimated yield operationunit may calculate an estimated yield in every step on the basis of olddata, calculate the number of normal products of every wafer group onthe basis of the estimated yield and calculate an estimated cost of thesemiconductor device on the basis of the number of normal products andthe working ratio of the production devices.

[0021] A production managing method for semiconductor devices, accordingto the present invention, comprises the steps of inputting at least dataof method for producing semiconductor devices, measured data,specifications of the process step corresponding to the measured data,data of lot input date and hour, data of scheduled process step date,data of actual date of completion in every step and data of scheduleddate of completion of the semiconductor devices, all of which areinputted by a user through a user terminal for every wafer groupincluding at least one wafer, storing the data of method for producingsemiconductor devices, the measured data, the specifications of the stepcorresponding to the measured data, the data of lot input date and hour,the data of scheduled process step date, the data of actual date ofcompletion in every step and the data of scheduled date of completion ofthe semiconductor devices in a database, performing process processingcorresponding to the process steps performed sequentially in each of aplurality of production devices, measuring process parameterscorresponding to process in every of the process steps, calculating anestimated yield, which is a final yield, in every wafer group on thebasis of the measured parameter data and the specification in every stepand storing these data for every wafer group in the database, whereinthe production management of the semiconductor devices ordered by theuser is performed on the basis of the respective data inputted by theuser and the estimated yield.

[0022] A production managing program of the present invention, forperforming a semiconductor production management by using the productionmanaging system mentioned above, comprises the steps of inputting atleast the data of method for producing semiconductor devices, themeasured data, the specifications of the process step corresponding tothe measured data, the data of lot input date and hour, the data ofscheduled process step date, the data of actual date of completion inevery step and data of scheduled date of completion of the semiconductordevices, all of which are inputted by the user through the user terminalfor every wafer group including at least one wafer, storing the methoddata, the measured data, the specifications of the step corresponding tothe measured data, the data, of lot input date and hour, the data ofscheduled process step date, the data of actual date of completion inevery step and the data of scheduled date of completion of thesemiconductor devices in the database, performing process processingcorresponding to process steps performed sequentially in each of theproduction devices, measuring process parameters corresponding toprocess in every process step, calculating an estimated yield, which isa final yield, in every wafer group on the basis of the measuredparameter data and the specification in every step and storing thesedata for every wafer group in the database, wherein the productionmanagement of the semiconductor devices ordered by the user is performedby a computer on the basis of the respective data inputted by the userand the estimated yield.

BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Embodiments of the present invention will be described withreference to the accompanying drawings, in which:

[0024]FIG. 1 is a block diagram showing a construction of a productionmanaging system for semiconductor devices, according to an embodiment ofthe present invention;

[0025]FIG. 2a and FIG. 2b are conceptual figures for explaining ameasurement of a bottom area of a contact hole by means of electron beamin a device used as an example of an in-line test device 12 a shown inFIG. 1;

[0026]FIG. 3a and FIG. 3b are conceptual figures for explaining ameasurement of a bottom area of a contact hole by means of electron beamin a device used as an example of an in-line test device 12 b shown inFIG. 1;

[0027]FIG. 4a and FIG. 4b are conceptual figures for explaining ameasurement of a width of a wiring formed of an electrically conductivematerial by means of electron beam in a device used as an example of anin-line test device 12 c shown in FIG. 1;

[0028]FIG. 5 is a conceptual figure of a wafer for explaining measuringposition data indicative of a measuring position within the wafer;

[0029]FIG. 6 is a conceptual figure for explaining element data of anelement to be measured;

[0030]FIG. 7 is a conceptual figure showing a setting table showing anupper and lower limits of a range of specifications of respectiveprocess parameters in every step;

[0031]FIG. 8 is a conceptual figure showing Poisson distribution used inobtaining a range of the standardized parameters;

[0032]FIG. 9 is a conceptual figure for explaining a flow for obtainingthe step yield at a finished time in every step;

[0033]FIG. 10 is a table showing upper limit/lower limit values ofprocess parameters in every step;

[0034]FIG. 11 is a table showing a range of minimum line width, whichcan be manufactured in each line, for setting a production line;

[0035]FIG. 12 is a table showing selectable production method forselecting a lot production method;

[0036]FIG. 13 is a step managing table for performing a lot productionmanagement by a production managing unit 1 b;

[0037]FIG. 14 is a step managing table for performing a lot productionmanagement by a production managing unit 1 b;

[0038]FIG. 15 is a table showing a portfolio construction of a lot underproduction;

[0039]FIG. 16 is a flowchart of a portion of a semiconductor deviceproduction managing system, in which a process selection of a lot isperformed;

[0040]FIG. 17 is a flowchart of a portion of the semiconductor deviceproduction managing system, in which a throwing-in of a new lot isperformed;

[0041]FIG. 18 is a flowchart of a portion of the semiconductor deviceproduction managing system, in which a production management of alreadythrown-in lot is performed;

[0042]FIG. 19 is a conceptual figure showing a screen to which a user IDand a password are inputted;

[0043]FIG. 20 is a conceptual figure showing a screen for performing theprocessing selection by the user in the flowchart shown in FIG. 16;

[0044]FIG. 21 is a conceptual figure showing a screen for performing aselection of course for performing a division of lot; and

[0045]FIG. 22 is a conceptual figure showing a screen for selectingsubsequent production of the lot.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0046]FIG. 1 is a block diagram showing a construction of a productionmanaging system of semiconductor devices according to an embodiment ofthe present invention.

[0047] The semiconductor device production managing system of thepresent invention is basically constructed with a semiconductorproducing center C and a plurality of user terminals U1, U2, U3, . . . ,which are connected to the semiconductor producing center C through aninternet.

[0048] The semiconductor producing center C includes a production line10, a server 1 and a database 2 are provided. The server 1 is connectedto the user terminals U1, U2, U3, . . . , which are constructed withpersonal computers, etc., respectively, through an informationcommunication line I.

[0049] The information communication line I may be an internet, ISDN(Integrated Services Digital Network) or public telephone line, etc.

[0050] The server 1 transmits data to and receives data from the userterminals U1, U2, U3, . . . , through the information communication lineI.

[0051] The production line 10 includes production devices 11 a, 11 b, 11c, . . . , for performing respective process steps for producingsemiconductor devices. The production devices are arranged in series inthe order of the process steps of a production method.

[0052] In the production line 10, in-line testers 12 a, 12 b, 12 c, . .. , are provided next to the respective production devices 11 a, 11 b,11 c, . . . .

[0053] The in-line testers 12 a, 12 b, 12 c, . . . , measure processparameters of chips located in predetermined positions of a wafer orwafers in a lot in the respective process steps executed by therespective production devices 11 a, 11 b, 11 c, and output result of themeasurement as measured data, respectively.

[0054] The most important feature of the present invention is that themeasured data obtained by the in-line testers 12 a, 12 b, 12 c, . . . ,are stored in the database 2 correspondingly to a lot number of the lotand a user who inputs the lot flowing through the production line 10performs the production management of the lot through the informationcommunication line I on the basis of test data stored in the database 2,by himself.

[0055] In this specification, the term “lot” means a processing unit ofproduction regardless of the number of wafers in the lot.

[0056] That is, in a case where only one wafer is flown as a unit when alot is divided or when a trial production is performed, semiconductordevices are produced on the one wafer through process stepsindependently from other lots, so that it is necessary to perform theproduction management for the one wafer as a lot.

[0057] In such case, values of specifications of the process parametersassigned by the user are used.

[0058] The server 1 calculates a step yield (for example, indicated by %unit) in every process step on the basis of the specifications, themeasured data and correction values and the calculated step yields arestored together with wafer number data indicative of the number of thewafers constituting each lot in the database 2 correspondingly to thelot number of every lot.

[0059] A final estimated yield of the production line is calculated bythe estimated yield operation unit 1 a of the server 1 at a time whenall of the process steps are completed on the basis of the step yieldsin the respective process steps, which are obtained by comparing themeasured data obtained by the in-line testers after each process step iscompleted with the corresponding specifications, under assumption thatstep yields in all of subsequent process steps are 100%, respectively.

[0060] Therefore, the user can confirm the number of the semiconductordevices, that is, the chips, which can be delivered finally, on thebasis of the estimated yield calculated every time when the process ofeach step is completed.

[0061] That is, in the semiconductor device production managing systemof the present invention, the user can confirm the estimated number ofthe semiconductor devices, which can be finally delivered, at the timewhen the respective process steps of the inputted lot are completed and,when the estimated number of the semiconductor devices is smaller thanthe desired number, can perform the production management such as inputof a new lot.

[0062] Returning to FIG. 1, the construction of the production managingsystem of semiconductor devices, according to the present invention willbe described in more detail.

[0063] The production device 11 a may be a device for formingthrough-holes in an insulating film by etching the insulating film of asemiconductor device subsequent to a photolithographic processingtherefor.

[0064] That is, the production device 11 a forms contact holes orvia-holes in the insulating film for connecting a diffusion layer (or awiring layer) formed on one surface of the insulating film to a wiringlayer formed later on the other surface of the insulating film.

[0065] The production device 11 a performs the step of painting an uppersurface of the insulating film with resist and the step of forming apatterned contact holes in the resist film by a photolithographicprocessing with using a mask having the contact hole pattern.

[0066] Further, the anisotropic etching of the contact hole pattern ofthe resist film is performed by an etching device of the productiondevice 11 a to form the patterned contact holes in the insulating film.

[0067] That is, the production device 11 a may be constructed with, forexample, a stepper for performing the photolithographic processing andthe etching device.

[0068] Incidentally, before the anisotropic etching step performed inthe production device 11 a, the diffusion step for diffusing impurity ina silicon substrate and the insulating film depositing step fordepositing a silicon oxide film on the upper surface of the diffusionlayer as an interlayer insulating film are performed.

[0069] In FIG. 1, a device for forming the insulating film and otherdevices such as an ion plantation device are not shown.

[0070] The production device 11 b may be a CVD (Chemical VaporDeposition) device for depositing an electrically conductive thin film,which is patterned to form a wiring between transistors.

[0071] Further, the production device 11 c may be used to pattern thethin film deposited by the production device 11 b.

[0072] That is, the production device 11 c is a device for etching theelectrically conductive thin film subsequent to the photolithographicprocessing to form the wiring pattern.

[0073] In the production device 11 c, the step of painting an uppersurface of the electrically conductive thin film with resist materialand the step of forming the wiring pattern in the resist film byperforming a photolithographic processing with using the mask having thewiring pattern are performed.

[0074] The anisotropic etching step for patterning the wiring resist isperformed by the etching device of the production device 11 c to formthe contact holes corresponding to the pattern in the insulating film.

[0075] That is, the production device 11 c may be constructed with, forexample, a stepper for performing the photolithographic processing andthe etching device.

[0076] The in-line tester 12 a measures, as the process parameters ofthe process steps performed by the production device 11 a, diameters ofthe patterned contact-holes formed in the resist film after thephotolithographic processing, which is preceding the etching step bymeans of the etching device, is performed and bottom areas of thecontact-holes formed in the insulating film after the etching isperformed by the etching device and outputs the diameters and the bottomareas of the contact-holes to the server 1 as the measured data togetherwith the lot number.

[0077] That is, as shown in FIG. 2A, the contact-hole 43 or a via-hole,which is not shown, is irradiated with an electron beam 31. In thiscase, when the contact hole or via hole is circular, the electron beam31 may have a rectangular cross section having longer side larger thanthe diameter of the contact hole or via-hole.

[0078] An electric current generated by irradiation of the electron beam31 is detected by an ammeter 9 of the in-line tester 12 a.

[0079] In this case, when the electron beam 31 irradiates the insulatingfilm 41, a minute current flowing through the insulating film 41 isdetected.

[0080] On the other hand, when the electron beam 31 irradiates thecontact hole 43, the underlying semiconductor substrate 42 is irradiatedwith the electron beam 31. Therefore, a current, which is larger thanthat detected when the electron beam 31 irradiates the insulating film41, is detected by the ammeter 9 (FIG. 2B).

[0081] That is, the in-line tester 12 a measures the current flowingcorrespondingly to the area of a portion of the underlying substrate 42,which is exposed through the contact hole 43 and the bottom area of thecontact hole 43 can be estimated by comparing an integrated value of themeasured current with an integrated current value preliminarily obtainedfor a unit area.

[0082] Alternatively, when an electron beam 51 having cross sectionalarea larger than an area of the contact hole 43 or a via-hole is used asshown in FIG. 3A, a current, which is large compared with thatobtainable when the insulating film 41 is irradiated with the electronbeam, is detected by the ammeter 9 as shown in FIG. 3B similarly to thecase shown in FIG. 2A or 2B.

[0083] Since, in the latter case, it is possible to measure the currentof the whole contact hole simultaneously, the detection current has avalue corresponding to the bottom area of the contact hole.

[0084] Alternatively, the bottom area of the contact hole 43 may beestimated by preliminarily measuring an integrated value of currentgenerated in a unit area by electron beam and comparing the integratedvalue with the current value measured by the in-line tester 12 a.

[0085] The in-line tester 12 b measures thickness of the deposited thinfilm and a sheet resistance of the thin film as the process parametersof the process steps of the production device 11 b and outputs theparameters to the server 1 together with the lot number.

[0086] The in-line tester 12 c measures width of the wiring pattern ofthe resist after the photolithographic processing step, which ispreceding the etching step in the etching device, is performed anddetermines an existence of a wiring defect after the etching step by theetching device, as the process parameters in the steps of the productiondevice 11 c, and outputs the width and the existence to the server 1together with the lot number.

[0087] In this case, the measurement of the width of the wiring patternof the resist may be performed by using a stylus type device.

[0088] As to the existence of the wiring defect after the etching step,it is determined by using electron beam similarly to the in-line tester12 a, as shown in FIG. 4A and FIG. 4B. In FIG. 4A and FIG. 4B, areconceptual figures for explaining the test for determining an existenceof the wiring pattern defect by means of electron beam and,particularly, the test in a case where the wiring pattern havinglongitudinal line portions of identical configuration, in which FIG. 4Ashows a case of a normal chip and FIG. 4B shows a case of abnormal chiphaving a wiring pattern defect.

[0089] In FIG. 4A and FIG. 4B, electron beam having a rectangular crosssectional area, which is 10 nm wide in a scan direction and several μmlong, irradiates measuring areas of the respective chips.

[0090] Current value obtainable by the current measuring method, whichis the principle of this measuring method, is a total value of currentsgenerated in the wiring patterns, which are irradiated simultaneouslywith electron beam.

[0091] That is, the in-line tester 12 c measures a current value, whichis a total current obtained as a sum of currents generated when therespective pattern portions of the wiring pattern are irradiated withelectron beam having a line rectangular cross sectional area.

[0092] In the examples of measurement shown in FIG. 4A and FIG. 4B, whenelectron beam 161 passes through positions a to positions b of thepattern 162 and 164, currents having similar values are detectedregardless of the quality of chip.

[0093] On the other hand, when the electron beam 161 passes throughpositions c to positions d, current due to the wiring 163 is measured inthe normal chip while current measured due to the wiring 165 of theabnormal chip is smaller than the current measured due to the normalchip.

[0094] Therefore, there is a considerable difference in waveform betweenthe normal and abnormal chips on which an existence of a wiring patterndefect 166 is detected.

[0095] That is, it is possible to detect an abnormal chip and specify adefective position thereof by scanning the chip with the electron beam161 even when the defect thereof is a positional overlapping of thewiring.

[0096] In the above mentioned measurement, the process parameters aremeasured in every step by selecting a plurality or all of the wafers ineach lot and performing the measurement at chips located in a pluralitypositions of each wafer in the lot.

[0097] As shown in FIG. 5, the measuring positions are preliminarilyassigned by the user as measuring regions A indicative of the chips inthe wafer to be measured. Measuring position data indicative of themeasuring positions is inputted by the user through the user terminal U1to the semiconductor producing center C and stored in the database 2thereof correspondingly to the lot number by the server 1.

[0098] Further, the user can select configuration and kind of anelement, which can be used to calculate a clear estimated yield in everylot, from TEG (Test Element Group) arranged in each chip and indicatedby the measuring position data for every process parameter.

[0099] For example, in a case where a bottom area of a contact hole isto be measured, the user selects one of test elements TS1, TS2 and TS3of circular contact holes having different diameters, as shown in FIG.6, which is suitable in a current lot.

[0100] The element data indicating this measuring element is inputted bythe user to the user terminal U1, transmitted to the server 1 and storedin the database 2 together with the lot number.

[0101] Further, the in-line testers 12 a, 12 b, 12 c, . . . , determinewhether or not the measured data of every chip of the wafers measured inevery step are within predetermined ranges of specifications and outputa result of the determinations to the server 1.

[0102] The specifications are set in every step corresponding to theprocess flow to every lot, as shown in FIG. 7.

[0103]FIG. 7 is a conceptual figure showing a setting table indicativeof an upper and lower limits of a range of each specification in everystep. In FIG. 7, a center value means a center value of each processparameter when a usual step processing is performed in each productiondevice, that is, a peak value of a Poisson distribution such as shown inFIG. 8.

[0104] The range of the specification shown in FIG. 7 in which themeasured data are to be fallen is determined by standardizing a range Lof the measured value in FIG. 8. That is, a standardized value STDA inFIG. 7 is obtained by standardizing the measured value A in FIG. 8 and astandardized value STDB in FIG. 7 is obtained by standardizing themeasured value B in FIG. 8.

[0105] With using the table shown in FIG. 7, the user defines the rangeof specification between the standardized values STDA and STDB in everystep.

[0106] The estimated yield operation unit 1 a counts the number ofnormal products fallen in the hatched area shown in FIG. 9 after eachstep is completed.

[0107] That is, the measured data of chips are arranged from minimum tomaximum and counts the chips having measured data fallen in the rangebetween the upper limit value STDA and the lower limit value STDB asnormal chips.

[0108] Incidentally, ordinate in FIG. 9 indicates the standardizedmeasured value and abscissa indicates the number of chips when thestandardized measured values are arranged from minimum to maximum. Whena plurality of chips having identical measured values exist, these chipsare numbered by different numbers.

[0109] By dividing the number of normal products by the number ofmeasured products in every wafer, it is possible to obtain a waferyield. Further, by dividing the number of normal products in a lotincluding the measured chips in the respective wafers by the number ofthe measured chips of the lot, a lot yield can be obtained.

[0110] A relation between the range of the specification and the numberof normal chips is stored in the database 2, correspondingly to the lotnumber as shown in the table in FIG. 10.

[0111] In FIG. 10, the range of the specification of process parametersis shown in every process step number.

[0112] For example, the process step 1 a may be the photolithographicstep of forming a resist pattern of contact holes when the contact holesare formed.

[0113] Since one of the process parameters in the step 1 a is a diameterof a hole of the contact hole pattern, the range of the specificationmay be defined by the user as an upper limit value of 2 μm and a lowerlimit value of 1.5 μm. Numerical values parenthesized in the upper andlower limit columns are standardized upper limit value STDA andstandardized lower limit value STDB.

[0114] Similarly, the step 1 b may be the etching step of forming thecontact holes by etching the insulating film down to the diffusion layerwith using the resist pattern formed in the step 1 a.

[0115] Further, since the process parameter in the step 1 b is a bottomarea of the contact hole formed in the insulating film, the upper limitvalue of 12.6 μm² and the lower limit value of 7 μm² of thespecification range of the bottom area are defined by the user.

[0116] The item “Flat Region Start Position” in the step 1 a shown inthe table in FIG. 10 indicates a chip number of a chip having contacthole diameter equal to or larger than the lower limit value of thespecification range and the item “Flat Region End Position” indicates achip number of a chip having contact hole diameter larger than the upperlimit value of the specification range.

[0117] On the basis of this table, all chips measured in a lot arearranged in a sequence from one having minimum contact hole diameter toone having maximum contact hole diameter and numbered in a similarmanner to that shown in FIG. 9 and the estimated yield operation unit 1a calculates the normal chips having contact hole diameters fallen inthe specification range of the lot.

[0118] The number of normal products can be obtained by an equation[(chip number in the flat region end position)−(chip number in the flatregion start position)].

[0119] That is, the estimated yield operation unit 1 a obtains the stepyields at ends of the respective steps by selecting a plurality ofwafers (or all wafers) in the lot at ends of the respective steps,obtaining a total number of measured chips in the plurality of thewafers in the lot and dividing a total number of chips of the lot, whichhave contact hole diameters fallen within the specification range, bythe total number of the measured chips.

[0120] For example, in FIG. 9, it is assumed that the total number ofthe measured chips in the lot is 100. In such case, the step yield inthe step 1 a becomes 76%, which is obtained by dividing the number ofnormal chips (=80 (chip number in the flat region end position)−4(chipnumber in the flat region start position)) by 100.

[0121] Now, a calculation method of the estimated yield will bedescribed.

[0122] The estimated yield is obtained by multiplying the step yieldwith a correction value.

[0123] The correction value is obtained statistically on the basis ofthe past records and is a coefficient for determining whether or not thestep yield obtained in each step becomes the final yield at a time pointwhen all of the production steps are completed.

[0124] That is, the correction value is obtained by averaging valuesobtained by dividing the final yield by the step yields in therespective steps in a plurality of the past lots and is obtained inevery step.

[0125] Further, this correction value depends upon the kind of process(production line) and the inputting manner of lot production method).Therefore, the estimated yield operation unit 1 a selects one of aplurality of correction values in every step correspondingly to acombination of the production line and the production method.

[0126] The kind of process may include a design rule classifiedaccording to a table shown in FIG. 11.

[0127] In the “Production Line Number” column shown in FIG. 11, the linenumbers of production lines along which the production devices arearranged in a clean room.

[0128] The values shown in the “Design Rule” column are ranges of widthof such as a gate of MOS transistor in designing state and indicateproduction accuracy obtainable in the respective production lines.

[0129] Further, the inputting manner of lot includes a fast deliverypriority course production method 1), a delivered number priority course(production method 2), a total cost priority course (production method3) and a quality priority course (production method 4), for example, asshown in FIG. 12.

[0130] The fast delivery priority course is selected in a case wheresemiconductor devices to be incorporated in some products for purpose oftrial manufacture are produced and the processing speed of thesemiconductor devices in a selected production line 10 (FIG. 1) areperformed as a matter of the highest priority, while neglecting thenumber and quality of delivered normal products.

[0131] Therefore, the cost per semiconductor device produced by the fastdelivery date priority course becomes very high.

[0132] In the delivery number priority course, the processing isperformed at a standard speed in the production line 10 and the numberof the normal products delivered on the appointed date of delivery isconsidered as a matter of the highest priority.

[0133] In the total cost priority course, the required processing isperformed along a selected production line 10 during a time zone orzones in which the production line is not at work. Therefore, it ispossible to reduce the production cost since the unused time zone of theproduction line 10 can be utilized effectively although it takes longtime to complete the production.

[0134] That is, according to the total cost priority course, it ispossible to reduce the cost per semiconductor device although theproduction time becomes long.

[0135] In the quality priority course, the processing of a lot isperformed after the processing of the respective process steps in therespective production devices 11 in the respective production lines 10are checked preliminarily. Therefore, the cost per semiconductor devicebecomes very high since the processing times in the respective stepsbecomes considerable and the process checks are troublesome.

[0136] Further, since, in the quality priority method, the specificationranges of the measured process parameters in the respective steps arereduced in order to improve the quality of the semiconductor products tobe delivered, the number of normal chips obtainable from a lot isreduced and the cost per chip becomes very high although thesemiconductor chips having specifications satisfying a user can berealized.

[0137] Therefore, when, for example, the estimated yield is obtainedfrom the step yield in the step 1 b for forming the contact holes byetching, the correction value to be multiplied with the step yield whenthe semiconductor devices are produced by a production line 2 (FIG. 11)is set to 0.1 for the fast delivery priority course 1, to 0.8 for thedelivery number priority course 2, to 0.9 for the total cost prioritycourse 3 and to 0.2 for the quality priority course 4.

[0138] The reason for why the correction value for the fast prioritycourse 1 is small is that the final yield becomes very low because, inorder to produce the semiconductor devices with delivering date as amatter of the highest priority, the specification range is widened andthe production is continued using values out of the specification rangesof normal product as reference values.

[0139] The reason for why the correction value for the quality prioritycourse 4 is small is that the number of normal products is substantiallyreduced and the final yield becomes low because, in order to produce thesemiconductor devices with quality as a matter of the highest priority,the specification range is narrowed and the manufacturing is continuedusing the specification range, which is narrowed compared with theconventional specification range of normal product as reference values.

[0140] The selections of the production line and the production methodare performed by using a user terminal such as the user terminal U1correspondingly to the design rule of the lot and the application of thechip to be produced by the user.

[0141] The data set by the user in the format shown in FIG. 13 is storedin the database 2.

[0142] In FIG. 13, the “Order Form” and the “Process Steps” are storedcorrespondingly to the name (CCCI) of user who orders the production.

[0143] The order form column includes “Name of Product”, “Lot Number”,“Production Method” and “Line Name” columns.

[0144] In the “Product Name” column, a product name (alpha) is indicatedand, in the “Lot Number” column, a lot number (XX) is indicated.

[0145] Further, in the “Production Method” column, the course (fastdelivery date priority) selected for the lot by the user from theproduction method courses shown in FIG. 12 is indicated, as an example.

[0146] In the “Line Name” column, a production line number (productionline 1) selected by the user from the production lines shown in FIG. 11correspondingly to the design rule of the lot is indicated.

[0147] In the “Process Steps” column of the selected production line onthe right side of the order form column, only the process steps 1 a and1 b are included in the sequence of the process flow, that is, in asimilar sequence to that shown in FIG. 10.

[0148] The process step 1 a is the photolithographic step for patterningthe contact holes, and the process step 1 b is the etching step forforming the contact holes, etc., for example. Other process steps aresimilarly indicated although not shown.

[0149] In each of the process step columns, “Prearranged Date”, “Date ofCompletion” and “Estimated Yield” columns are included.

[0150] The prearranged date (data of prearranged date on which therelated process step is performed) is a prearranged date for performingthe process step in every lot, which is obtained on the basis of theinput date of lot, the data of requested date of completion and the kindof production method, which are inputted by the user after theproduction managing unit 1 b performs a regulation with respect to otherlots, which are being processed in other production lines assigned bythe user.

[0151] That is, the production managing unit 1 b detects a date on whichthe processing is possible in a “processing schedule table” of everyprocess step on the basis of the kind of production method, the lotinput date and the requested date of completion, which are inputted bythe user, calculates the prearranged date for the processing of the lotcorresponding to these data and stores the calculated prearranged datein the database 2 correspondingly to the lot number.

[0152] The processing schedule table is a schedule table showing aprocessing date and hour schedule of a lot flowing through a productionline in every step of the production line and is produced by theproduction managing unit 1 b.

[0153] The production managing unit 1 b performs the process stepmanagement of the respective lots by managing the operations of therespective production devices 11 a, 11 b, 11 c, . . . , on the basis ofthe processing schedule table and transmits the measured data of theprocess parameters corresponding to the respective steps, which aremeasured by the in-line testers 12 a, 12 b, 12 c, . . . , to the server1 after the respective process steps are completed.

[0154] The server 1 stores the measured data from the productionmanaging unit 1 in the database 2 correspondingly to the respectivelots.

[0155] The “date of completion (completion date data)” column indicatesa date on which the process steps for the lot are actually executed andthis column is blank (data is not inputted) for a lot the process stepsof which are not completed.

[0156] The estimated yield column indicates an estimated yield obtainedby the above described estimated yield calculation performed on thebasis of measured data measured after the step processing in, forexample, the step 1 a is completed.

[0157] The table shown in FIG. 13 is displayed on a display screen ofthe user terminal U1 (or U2, U3) when the user asks for progress of thelot by inputting the lot number through the user terminal U1 (or U2,U3).

[0158] In this case, the server 1 extracts a block of data correspondingto the lot number inputted by the user through the user terminal U1,that is, the respective data shown in the table in FIG. 13, from thedatabase 2 and outputs the data block to the user terminal U1.

[0159] The respective data of the requested lot sent from the server 1are displayed on the display screen of the user terminal U1 in the tableformat shown in FIG. 13.

[0160] The table shown in FIG. 10 is displayed on the display screen ofthe user terminal U1 by clicking “prearranged date”, “completion date”and “estimated yield” columns in the process step 1 a in the table shownin FIG. 13 by using a mouse.

[0161] Correspondingly to the clicked column of the process step in FIG.13, a background color of the process step column in the table shown inFIG. 10 is changed, so that the user can confirm the measured data ofthe corresponding process steps and the specifications of the processparameters, etc.

[0162] In this case, the server 1 extracts data blocks of the respectiveprocess steps in the lot corresponding to the lot number requested bythe user, that is, the respective data shown in FIG. 10, from thedatabase 2 on the basis of the lot number inputted by the user throughthe user terminal U1 and outputs them to the user terminal U1.

[0163] The respective data of the lot outputted from the server 1correspondingly to the requested lot number is displayed on the displayscreen of the user terminal U1 in the table format shown in FIG. 10.

[0164] Further, by clicking “lot number” column in the table shown inFIG. 13, a table shown in FIG. 14 is displayed.

[0165] In this case, the server 1 extracts data blocks of the respectivesteps in the lot corresponding to the lot number requested by the userthrough the user terminal U1, that is, the respective data shown in FIG.14, from the database 2 on the basis of the lot number inputted by theuser through the user terminal U1 and outputs them to the user terminalU1.

[0166] Then, the respective data of the lot outputted from the server 1correspondingly to the requested lot number are displayed on the displayscreen of the user terminal U1 in the table format shown in FIG. 14.

[0167] The table shown in FIG. 14 shows the history of productionprocess of semiconductor devices of every lot and shows respective data,which become the base of the production management by the user. The datashown in this table will be described sequentially.

[0168] In a column corresponding to “calculation date”, the date onwhich data to be described are written in.

[0169] In a column corresponding to “current process step”, names ofprocess steps such as “lot input date” on which a lot is thrown-in and“contact (steps 1 a and 1 b)”, etc., are indicated.

[0170] In the column “prearranged date of completion (data ofprearranged date of completion)”, either a desired date of completioninputted by the user or a prearranged date of completion calculated bythe production managing unit 1 b at a time when the processing in therespective process steps is completed.

[0171] The production managing unit 1 b obtains a prearranged date ofcompletion after regulations in the prearranged processing table of therespective steps on the basis of the lot input date (data of lot inputdate and hour), a desired date of completion (data of desired date ofcompletion) and the kind of production method and stores the prearrangeddate of completion in the database 2 correspondingly to the lot number.

[0172] This prearranged date of completion is usually calculated by theproduction managing unit 1 b and is changed at an end of the processstep on the basis of the working rate of the production line throughwhich the lot is flowing and regulations with respect to other lots.

[0173] In the column “expected number of delivery”, an expected numberof normal semiconductor devices, which is calculated by the estimatedyield operation unit 1 a on the basis the estimated yields calculated atend times of the respective steps and a total number of chips of thelot, is indicated.

[0174] In the “unit cost of chip” column, a cost per normalsemiconductor device (chip), which is obtained in the estimated yieldoperation unit 1 a by dividing the “total cost” of the production ofthis lot by the prearranged number of normal chips, is indicated.

[0175] In this case, the estimated yield operation unit 1 a estimates afinal cost of the semiconductor device at the end time of every processstep.

[0176] In the “total cost” column, the above mentioned total cost of theproduction of the lot is indicated.

[0177] When some change is performed in the processing in the processsteps in the lot, a description corresponding to that change isindicated in the “remarks” column.

[0178] For example, when the width of the resist pattern is deviatedfrom the specification range and the estimated yield calculated is verylow in the photolithography step 3 a in the wiring step, thephotolithography step must be performed again.

[0179] When the user notifies the server 1 of the re-try of the wiringstep, the server 1 must control the production process in order toremove the resist and to perform a new photolithographic process.Therefore, a character data “100% re-operation selected” is indicated inthe remarks column.

[0180] The production managing unit 1 b regulates the date and hour forthe re-operation of the photolithography step on the basis of theprocessing schedule table.

[0181] In such case, the server 1 indicates a character data “100%re-operation” in the remarks column in order to perform the newphotolithography step.

[0182] The estimated yield operation unit 1 a operates a new estimatedyield at the end point of the re-processing in this step, updates thedata by calculating the prearranged delivery number of products and theunit cost of chip again on the basis of the newly estimated yield andindicates the updated data in the corresponding column.

[0183] As described, the production managing system for semiconductordevice, according to the present invention, is constructed with thesemiconductor producing center C, which is connected to the userterminals through the information communication line and includes theplurality of the production devices 11 a, 11 b, 11 c, . . . , thein-line testers 12 a, 12 b, 12 c, . . . , provided next to therespective production devices for measuring the process parameterscorresponding to the process steps performed in the respectiveproduction devices and outputting the results of the measurements as themeasured data in units of lot, the database 2 for storing the managingdata of every lot, which include the production method data, themeasured data, the specifications of the process steps corresponding tothe measured data, the estimate yield, the data of lot input date, thedata of scheduled date of process step, the data of the process stepcompletion date and the data of the prearranged date of completion ofthe semiconductor devices, etc., which are described with reference toFIG. 5 to FIG. 15, in every process step corresponding to the lot numberassigned to the lot of the semiconductor devices (that is, in everyprocess step in a region of the wafers corresponding to the lot number)and the server 1 including the estimated yield operation unit 1 a forcalculating the estimated yield on the basis of the specifications andthe measured data and the production managing unit 1 b for managing theproduction of the ordered semiconductor devices on the basis of themanaging data and the data of desired date of completion.

[0184] The server 1 performs write and read of the specifications, thedesired date of completion (desired completion date data) and the lotinput date (data of the lot input date), which are inputted by the userthrough the user terminals U1, U2, U3, and the managing data withrespect to the database 2.

[0185] The table of a wafer input portfolio shown in FIG. 16 isdisplayed on the display screen by clicking the region in the “productname” column shown in FIG. 13 in which the product name is indicated.

[0186] In this case, the server 1 extracts, from the database 2, thedata showing the construction of the wafer input portfolio correspondingto the product name requested by the user, that is, the data shown inthe table in FIG. 15, on the basis of the product name inputted by theuser through the user terminal U1 and outputs the extracted data to theuser terminal U1.

[0187] The respective lot data outputted from the server 1correspondingly to the requested product name is displayed on thedisplay screen of the user terminal U1 in the table format shown in FIG.15.

[0188] That is, when the lot is processed according to the portfolioconstruction, a group of wafers is formed by one product name.Therefore, all of the lot numbers of a group in one product name aredisplayed in FIG. 15 even when the lot having the lot number in theproduct name group is to be confirmed in performing the productionmanagement.

[0189] Therefore, the user is required to confirm the prearranged numberof normal products in individual lot on the basis of the prearrangeddelivery number of products in the table shown in FIG. 14.

[0190] In the table shown in FIG. 15, products having an identicalproduct name are produced in a plurality of lots. Although there is acase where the lots are different lots, the products may be produced bydividing one lot to a plurality of sub lots.

[0191] For example, in a case where one lot can sufficiently cover a sumof the number of chips necessary to be produced quickly as engineeringsamples (ES), the number of chips necessary to be delivered as samplesand the number of chips necessary for reliability test, the requiredproduction method is assigned by dividing one lot to a plurality of sublots and assigning the sub lots to different processes.

[0192] For example, in FIG. 15, the semiconductor devices having theclicked product name are produced by dividing a lot having lot number“XX” to three sub lots numbered “XXA”, “XXB” and “XXC” and assigning theproduction method 1, the production method 2 and the production method 3to the three sub lots, respectively.

[0193] The item “Mixing Ratio %” in FIG. 15 indicates the constitutionalratio of the sub lots having lot numbers “XXA”, “XXB” and “XXC” in oneproduct name group.

[0194] Assuming that 10 wafers in the three sub lots having the sameproduct name are being produced, the number of wafers having sub lotnumber “XXA” is 6 since the mixing ratio thereof is 60%, the number ofwafers having sub lot number “XXB” is 2 since the mixing ratio thereofis 20% and the number of wafers having sub lot number “XXC” is 2 sincethe mixing ratio thereof is 20%.

[0195] In the “initial chip delivering date” column in FIG. 15, theprearranged date of completion in the course of the production methodwith which the semiconductor devices are completed most quickly andwhich is determined on the basis of the calculation of the prearrangeddates of completion in the respective production courses performed bythe production managing unit 1 b is indicated.

[0196] Further, the value in the “predicted number of normal products”column in FIG. 15 is a total number of normal products in all of theproduction courses, which is obtained on the basis of the prearrangednumber of delivered chips calculated in every sub lot by the estimatedyield operation unit 1 a on the basis of the estimated yields of therespective process steps.

[0197] In addition, the value in the “predicted chip cost” column inFIG. 15 is a result of calculation of unit cost of chip in each of thesub lots, which is obtained by averaging the unit chip costs for all ofthe sub lots constituting the estimated portfolio by the estimated yieldoperation unit 1 a.

[0198] That is, the wafer input portfolio shown in FIG. 15 is similar tothe portfolio usually utilized by stock companies and banks, etc., andindicates a combination of production methods of lots for obtainingchips as the working profit with low cost and high profit, byconsidering the number of finally obtainable chips (corresponding to theprofit with respect to investment) and the chip delivering date(corresponding to a term of investment).

[0199] By confirming the initial chip delivering date and the predictedchip cost, the user determines whether or not the number of chipsfinally required and the date on which the normal chips can be obtainedcorresponds to his request.

[0200] Now, an operation of the semiconductor device production managingsystem according to an embodiment of the present invention will bedescribed with reference to FIG. 16 to FIG. 18.

[0201]FIG. 16 is a flowchart showing an operation of the semiconductordevice production managing system for selecting one of the useroperations, that is, the input operation a new lot, and the operationfor performing the production management of the lot already thrown in.

[0202]FIG. 17 is a flowchart showing a flow of processing when the userinputs a new lot.

[0203]FIG. 18 is a flowchart shows a flow of processing for performingthe production management of the lot already thrown in by the user.

[0204] The flowchart shown in FIG. 16 will be described. In thisexample, it is assumed that an internet is used as the informationcommunication line I.

[0205] In the step S0, the user inputs URL (Uniform Resource Locator) ofthe semiconductor production center C from an input device such askey-board of the user terminal U1 to a browser provided in the userterminal U1 to connect the internet to the server 1 of the semiconductorproduction center C.

[0206] Next, in the step S1, the server 1 transmits an image of a webpage of the semiconductor device production center C as a display imageto the user terminal U1 in HTML format according to a program stored inan internal memory of the server 1.

[0207] The display image contains an input portion (authentication inputscreen) to which a user ID and a password, which are shown in FIG. 19,for confirming the user, are inputted.

[0208] Next, in the step S2, the user terminal U1 displays the displayimage of the web page transmitted from the server 1 by the browser ofthe user terminal U1 on the display screen thereof.

[0209] Then, the user inputs the preliminarily given ID number andpassword of the user, which are preliminarily registered in the server1, to the input portion shown in FIG. 19 on the display screen of theuser terminal U1.

[0210] Thus, the browser of the user terminal U1 transmits the inputtedID number and the inputted password of the user to the server 1.

[0211] Next, in the step S3, the server 1 determines whether or not theinputted ID number and password are registered on the database 2.

[0212] In this case, when the server 1 determines that the inputted IDnumber and password are not registered in the database 2, the operationis returned to the step S1 to allow the user to input the correct IDnumber and the correct password again.

[0213] When, for example, the input operation of one of the inputted IDnumber and the inputted password is erroneous a preset number of times,for example, three times, the server 1 stops a signaltransmission/receiving with the user terminal U1 once by cutting off thecommunication line.

[0214] On the other hand, when the server 1 determined that the inputtedID number and password are registered in the database 2 in the step S3,the server 1 transmits a processing content selection image shown inFIG. 20 to the user terminal U1 similarly to the authentication inputimage.

[0215] The processing content selection image shown in FIG. 20 includes“new lot input” and “production management”. The “new lot input”indicates the processing of input of a new lot and the “productionmanagement” indicates the processing of the production management of thelot, which was already thrown-in and is being flown through theproduction line.

[0216] Next, in the step S4, the user terminal U1 displays theprocessing content selection image shown in FIG. 20 and transmitted fromthe server 1 on its display screen.

[0217] The user can perform a requested processing by clicking any ofthe contents on the processing content selection image displayed on thedisplay of the user terminal U1.

[0218] In this case, the user terminal U1 transmits the informationselected by the clicking to the server 1.

[0219] Next, in the step S5, the server 1 determines the processingrequested by the user on the basis of the selected information inputtedfrom the user terminal U1.

[0220] That is, when the server 1 determines, in the step S6, that theselected information is the input processing of a new lot, the operationis shifted to the step S7 in which the processing A for inputting thenew lot is performed.

[0221] On the other hand, when the server 1 determines, in the step S8,that the selected information is the processing for performing theproduction management of the already flowing lot, the operation isshifted to the step S9 in which the processing B for the lot managementis performed.

[0222] Now, the processing of the newly inputted lot in the step S7 willbe described with reference to the flowchart shown in FIG. 17.

[0223] In the step S70, the server 1 determines the lot number of thelot to be newly thrown in and provides a data region of the new lot inthe database 2.

[0224] And then, the server 1 transmits an image of a selection tableshown in FIG. 12 for selecting one of the lot production methods and animage of the table shown in FIG. 11 for selecting one of the productionlines for treating the lot to the user terminal U1.

[0225] Then, in the step S71, the user terminal U1 displays, on itsdisplay screen, the image of the selection table and the image of thetable for selecting one of the production lines for treating the lot,which are transmitted from the server 1.

[0226] The user selects one of the production methods for the lot to benewly thrown in, by clicking one of “1: Fast Delivery Date Priority”course, “2: Number of Products Delivered on Date of Delivery Priority”course, “3: Total Cost Priority” course and “4: Quality Priority” coursein the image shown in FIG. 12.

[0227] Similarly, the user selects one of the production lines for thelot to be newly thrown by clicking one of “line 1: 0.1-0.13 μm”, “line2: 0.13-0.15 μm”, “line 3: 0.15-0.18 μm”, “line 4: 0.18-0.25 μm”, “line5: 0.25-0.35 μm” and “line 6: 0.35 μm or more” in the production lineselection table shown in FIG. 11.

[0228] In this case, the user inputs the input date of the lot to benewly thrown in and the desired date of completion to the user terminalU1 through the key board thereof, etc.

[0229] The user terminal U1 transmits the data of the selectedproduction method, the data of the selected production line, the data ofthe lot input date and the data of the desired date of completion to theserver 1.

[0230] Next, in the step S72, the server 1 stores the data of theselected production method, the data of the selected production line,the data of the lot input date and the data of the desired date ofcompletion inputted from the user terminal U1 in the database 2corresponding to the lot number newly registered.

[0231] The lot number of the lot to be newly thrown in is obtained bythe server 1 by adding “1” to the final lot number of the lot, which isbeing flown.

[0232] The server 1 transmits the image of the specification settingscreen shown in FIG. 7 for inputting the specification ranges in everyprocess step and the data of the lot number newly registered to the userterminal U1.

[0233] And then, in the step S73, the user terminal U1 displays thespecification setting image shown in FIG. 7 on its display screen andstores the given lot number in an internal managing table thereofcorrespondingly to the product name, the lot input date and the desireddate of completion.

[0234] The user inputs marginal values, that is, the specification rangein every process step by clicking the display screen with using such asa mouse.

[0235] In this case, the user may input the specification ranges of theprocess parameters sequentially through the keyboard of the userterminal in every step selected by clicking the specification rangesshown in FIG. 7.

[0236] And then, in the step S74, the server 1 stores the data of thespecification ranges of the respective steps inputted from the userterminal U1 in the database 2 correspondingly to the lot number of thelot, which is newly thrown in and registered.

[0237] And then, the server 1 transmits to the user terminal U1 aselection image for selecting the kind of test element, which hasparameters shown in FIG. 6 and is to be measured, and an image forselecting positions on the wafers to be measured.

[0238] Then, in the step S75, the user terminal U1 displays theselection image for selecting the kind of test element having parametersshown in FIG. 6 and the image for selecting positions on the wafers tobe measured on its display screen.

[0239] The user selects the test element to be used by clicking theimage for selecting the king of the test element displayed on thedisplay screen of the user terminal U1 and, simultaneously, selects themeasuring points on the wafer in every step by clicking the image forselecting positions on the wafers to be measured.

[0240] The user terminal U1 transmits the element data indicative of theselected element and the measuring position data indicative of positionson the selected measuring points to the server 1.

[0241] Thereafter, in the step S76, the server 1 stores the element dataand the measuring position data, which are inputted from the userterminal U1, in the database 2 correspondingly to the lot number of thelot newly thrown and registered.

[0242] In order to calculate the predicted number of normal productswhen the new lot is thrown in, the server 1 extracts the estimated yieldin the past combination of the production method and the productionline, on the basis of the production method course and the productionline from the database 2.

[0243] Then, when the lot is inputted, the server 1 calculates thepredicted number of normal products by multiplying the extractedestimated yield with a total number of chips of this lot.

[0244] The server 1 transmits the calculated predicted number of normalproducts when the new lot is thrown in to the user terminal U1.

[0245] In the step S77, the user terminal U1 displays the predictednumber of normal products transmitted from the server 1 on the displayscreen thereof.

[0246] The user confirms the displayed predicted number of normalproducts on the display screen of the user terminal and determineswhether or not a finally required number of chips can be obtained.

[0247] In this case, when the predicted number of normal products issmaller than the required number of chips, the user clicks a region“insufficient” on the display screen.

[0248] Thereafter, the user terminal U1 transmits a request datarequesting an input (re-input) of a new lot to the server 1 togetherwith the number of new lots.

[0249] In response to this request data from the user terminal U1, theserver 1 returns the operation to the step S6 and performs theprocessing in this step under the same product name with using adifferent lot number for the newly thrown lot. The lot input processingfor re-inputting lot is similar to that for the usual input processingof the lot as described previously.

[0250] That is, the estimated yield operation unit 1 a and theproduction managing unit 1 b of the server 1 produce a productionschedule on the basis of the desired date of completion, which isinputted by the user through the user terminal U1, and perform theprocessing such as calculation of data including the data of prearrangeddate of completion on the basis of the production schedule similarly tothe previously described case of the input of the lot.

[0251] In this case, the data of lot input date is made data of re-inputdate and the number of wafers, which is inputted, is made data of thenumber of re-inputted wafers. The data of re-input date and the data ofthe number of re-input wafers are stored in the database 2 correspondingto the lot number of the re-input lot and treated as an input of new lotas described above.

[0252] Further, in the step S77, the user can perform the dividingprocessing of the lot as shown in FIG. 21 after the predicted number ofnormal products is confirmed.

[0253] That is, when the user requests the server 1 of the dividingprocessing of the lot through the user terminal U1, the server 1transmits a selection table image of the dividing processing shown inFIG. 21 to the user terminal U1.

[0254] The user terminal U1 displays the selection table image of thedividing processing transmitted from the server 1 on its display screen.

[0255] The user selects a method for dividing the lot by clicking theselection table displayed on the display screen of the user terminal U1.

[0256] The selection table includes three kinds of courses, that is,“course 1” in which no division is performed, “course 2” in which thelot is divided by two and “course 3” in which conditional division isperformed.

[0257] The “course 1” in which the lot is not divided is the same as thecase where the lot is flown usually.

[0258] The “course 2” in which the lot is divided by two is used in acase where the desired number of chips must be obtained in a limitedterm. In such case, in order for diversification of risks, the lot isdivided to two sub lots (or to a plurality of sub lots on demand) andthe semiconductor devices are produced in the production lines bystaggering the processing time.

[0259] In the “course 3” of the conditional branching of the lot, onelot is divided to a plurality of sub lots and the production isperformed by changing the production method for the respective sub lotsso that the portfolio shown in FIG. 15 is realized by the one lot.

[0260] In this case, when the lot number of the lot before division is“XX” and the lot is divided to three sub lots, the lot numbers of thesub lots become “XXA”, “XXB” and “XXC”.

[0261] From this time point, the calculations of the respective dataincluding the process step management, the estimated yield, describedwith reference to FIG. 13 to FIG. 15, are started for the newly inputtedlot by the estimated yield operation unit 1 a and the productionmanaging unit 1 b.

[0262] That is, after the processing shown by the flowchart in FIG. 17,the process management of the lot is performed by the productionmanaging unit 1 b on the basis of the tables shown in FIGS. 13 and 14and the prearranged processing table of the process steps in theproduction line to which the lot is thrown (for example, any one of theproduction lines 1 to 6) and, after the processing of the respectivesteps are completed, the process parameters corresponding to therespective steps are measured by the in-line testers (12 a to 12 c).

[0263] The estimated yield operation unit 1 a calculates the data suchas the estimated yields at end times of the respective process steps onthe basis of the measured data.

[0264] Since, in the production managing system for semiconductordevices, according to the present invention, the final estimated yieldis calculated at the time when the lot is inputted, it is possible toeffectively utilize the lot dividing processing as described below.

[0265] In the present production managing system for semiconductordevices, the usual lot can be divided to a plurality of sub lots eachincluding the required number of chips on the basis of the estimatedyield at the time of the input of the lot and the execution times of thesub lots are staggered each other such that, when one of the sub lotsbecomes defective due to process problem and/or production device, asucceeding sub lot is executed. Therefore, it becomes possible toreliably produce the desired number of chips within a predetermined timeperiod.

[0266] Further, when the “course 3” in which the lot is conditionallydivided is used in the production managing system for semiconductordevices is used and the constructions of the portfolio are appropriatelycombined on the basis of the number of chips to be produced in differentproduction lines according to objects and the production times requiredthereby on the basis of the estimated yield at the times when the sublots are thrown in, it becomes possible to produce the engineering chipsrequired initially, which are to be produced quikly, the chips producedby the quality priority production method, which are necessary in thereliability test and the finally required chips within the respectiverequired time periods and with reduced total cost.

[0267] Further, although the portfolio has been described by dividingone lot to a plurality of sub lots, it is possible to perform theportfolio by using a plurality of lots in lieu of the sub lots since themanagement thereof is similar to the management of a plurality of lotsas a group under one “product name”.

[0268] Now, the processing of the production management of the alreadyinputted lot in the step S9 will be described with reference to theflowchart shown in FIG. 18.

[0269] In the step S90, the server 1 transmits an input image forinputting the lot number of the lot to be production managed to the userterminal U1.

[0270] Then, in the step S91, the user terminal U1 displays the inputimage transmitted from the server 1 on its display screen.

[0271] The user inputs the lot number of the lot, the production ofwhich is to be managed, on the displayed input image by using akeyboard, etc., of the user terminal U1.

[0272] The user terminal U1 transmits the data of the inputted lotnumber to the server 1.

[0273] In the step S92, the server 1 searches the database 2 on the stepmanagement table (FIG. 13) of this lot on the basis of the lot numberdata inputted from the user terminal U1.

[0274] And then, the server 1 transmits an image of the searched stepmanagement table to the user terminal U1.

[0275] In the step S93, the user terminal U1 displays the image of thestep management table shown in FIG. 13 inputted from the server 1 on itsdisplay screen.

[0276] And then, the user confirms the predicted date of stepcompletion, the actual date of step completion and the estimated stepyield for every step on the step management table of this lot anddetermines whether or not the required time period and the requirednumber of chips are in the satisfactory states by reading the tablesshown in FIG. 14 and FIG. 15 from the database 2 by using the stepmanagement table shown in FIG. 13 and confirming the prearranged date ofcompletion of the semiconductor devices, the unit cost of chip, thepredicted number of chips delivered, the total cost, the initial chipdelivering date, the number of normal products and the predicted chipcost.

[0277] In this case, when the numerical values in the respective tablesshown in FIG. 13 and FIG. 14 are satisfactory, the user performs the logout processing in the step S98 under consideration of re-confirmation onthe predicted date of completion of the next step and cuts off theconnection to the server 1.

[0278] On the other hand, when the numerical values in the tables shownin FIG. 13 and FIG. 14 are not satisfactory, the user must consider onthe production method and the continuation of the production of the lot.

[0279] For example, when the estimated yield of the lot number “XXA” ofone of the three sub lot, which is produced as the engineering samplesby the production method 1 is not satisfactory and an enough number ofnormal products can not be produced even if the production is performedcontinuously, the user changes the production method 2 of the lot number“XXB” to the production method 1.

[0280] When the estimated yield calculated after the step processingbecomes lower than the desired yield preliminarily set by the user andthere is no access from the user within a constant time period, forexample, within one day after the step providing the low estimated yieldis finished, the server 1 transmits a mail to the user terminal U1 fornotifying the calculated low estimated yield and the step correspondingto this estimated yield.

[0281] The desired yield is transmitted simultaneously with atransmission of the specifications of the respective steps in FIG. 7from the user to the server 1.

[0282] The server 1 stores the desired yield correspondingly to therespective steps of every lot number.

[0283] In this case, the user inputs, through the keyboard, etc., thelot number “XXB” and a changing instruction of the production method forthe lot number “XXB” and the lot number “XXA” and an instructionrequesting a selection whether or not the production of the lot havingthe lot number “XXA” is continued.

[0284] The user terminal U1 transmits the change request data forchanging the production method of the lot number “XXB” and the selectionrequest data requesting the determination of whether or not theproduction of the lot number “XXA” is to be continued to the server 1.

[0285] The, in the step S94, the server 1 transmits the step managementtable shown in FIG. 13 and a table shown in FIG. 22 for determiningwhether or not the lot production is to be continued further to the userterminal U1 on the basis of the change request data and the selectionrequest data, which are inputted from the user terminal U1.

[0286] In the step S95, the user terminal U1 displays the table shown inFIG. 13 corresponding to the lot having the lot number “XXB” and thetable shown in FIG. 22 corresponding to the lot having the lot number“XXA” on the display screen thereof.

[0287] The user displays the selection table shown in FIG. 12 byclicking the production method column of the FIG. 13 on the displayscreen of the user terminal U1 and clicks the production method to bechanged.

[0288] When the user clicks the production method 1, the productionmethod of the lot number “XXB” is changed from the production method 2to the production method 1.

[0289] The user terminal U1 transmits a production method changinginstruction including the data of the lot number of the lot in questionto the server 1.

[0290] Further, when the estimated yield of the lot number “XXA” isunsatisfactory and the production of that lot is to be stopped, the userclicks the region of “3 stoppage”.

[0291] The user terminal U1 transmits a production stop instruction forstopping the production of the lot number “XXA” to the server 1. Theproduction stop instruction includes the lot number of the lot inquestion.

[0292] In the step S96, on the basis of the inputted change instruction,the server 1 changes the data of the production method corresponding tothe lot having the lot number “XXB” in the database 1 from theproduction method 2 to the production method 1.

[0293] In this case, the estimated yield operation unit 1 are-calculates the estimated yield in every changed step of the changedproduction method and stores the re-calculated estimated yield and othernumerical values in the table shown in FIG. 14, which are calculated onthe basis of the re-calculated estimated yield in the database 2correspondingly to the lot number.

[0294] In this case, if the semiconductor devices are being produced bythe portfolio, the final predicted number of normal products in FIG. 15is re-calculated and the re-calculated final predicted number of normalproducts is stored in the database 2 correspondingly to the lot number.

[0295] The production managing unit 1 b performs a regulation in orderto make the processing schedule for the subsequent steps correspondentto the changed production method 1 of the lot number “XXB”.

[0296] Further, the server 1 outputs a stop instruction for instructingstoppage of the production of the lot number “XXA” to the productionmanaging unit 1 b on the basis of the inputted production stopinstruction.

[0297] The production managing unit 1 b advances the sequence of therespective process steps of the lot number “XXB” so as to make themcorrespondent to the production method 1, deletes the lot number “XXA”from the processing schedule of the respective steps and stops thesubsequent production of the lot having the lot number “XXA”.

[0298] The server 1 transmits the image data of the tables in FIG. 14and FIG. 15 corresponding to the lot number “XXB” to the user terminalU1.

[0299] In the step S97, the user terminal U1 displays the image data ofthe tables in FIG. 14 and FIG. 15 corresponding to the lot number “XXB”inputted from the server 1 on the display screen thereof.

[0300] The user determines, on the basis of the table shown in FIG. 14and the table shown in FIG. 15, whether or not the estimated yield, thepredicted number of normal products and the initial chip delivering dateare satisfactory.

[0301] When the values shown in the tables in FIG. 14 and FIG. 15 areunsatisfactory, the user repeats the processing in the step S93.

[0302] On the contrary, when the values shown in the tables in FIG. 14and FIG. 15 are satisfactory, the user shifts the operation to the stepS98 and cuts off the connection to the server 1.

[0303] On the other hand, when, in the step S93, the user determinesthat the estimated yield of the lot number “XXA” (after the step inwhich the confirmation is performed) is very high and the requirednumber of chips can be achieved by a half of the current number of chipsor smaller, the user inputs a selection instruction requesting aselection of continuation or stoppage of the production of the lotnumber “XXA” through the keyboard, etc.

[0304] The user terminal U1 transmits the selection request data for thelot having the lot number “XXA” to the server 1.

[0305] Then, in the step S94, the server 1 transmits the table shown inFIG. 22, for instructing continuation or stoppage of the production ofthe lot, to the user terminal U1.

[0306] In the step S95, the user terminal U1 displays the table in FIG.22 corresponding to the lot having the lot number “XXA” and transmittedfrom the server 1 on the display screen thereof.

[0307] The user clicks the region “2: 50% continue” in the table in FIG.22 displayed on the display screen to reduce the number of chips to beproduced to a half.

[0308] The user terminal U1 transmits a number change instruction formaking the number of the wafers (the chips) in the lot having the lotnumber “XXA” one second to the server 1. This number change instructionincludes the lot number of the lot in question.

[0309] In the step S96, on the basis of the number change instructioninputted from the user terminal U1, the server 1 outputs an instructioninstructing the reduction of the number of wafers in the lot having thelot number “XXA” to a half to the production managing unit 1 b.

[0310] Upon this, the production managing unit 1 b changes theprocessing number of the wafers in the lot having the lot number “XXA”in the subsequent steps to 50%.

[0311] The estimated yield operation unit 1 a calculates the prearrangeddelivery number of products, the cost of unit chip, the total cost andthe predicted number of normal products in the lot having the lot number“XXA” in the tables shown in FIG. 14 and FIG. 15 and stores thecalculated values in the database 2 correspondingly to the lot number“XXA”.

[0312] According to the schedule change in the respective stepssubsequent to the number change of the wafers of the lot having the lotnumber “XXA”, the production managing unit 1 b changes the data of theprearranged date of completion and the initial chip delivering date inthe database 2.

[0313] In the step S95, when the user determines that the predictednumber of normal products in FIG. 15 does not satisfy the requirednumber of chips, the user returns the display to that in the step S4,clicks the region for inputting new lot on the display screen in FIG. 20and inputs a new lot.

[0314] According to the production managing system of semiconductordevices of the present invention, the estimated yield is obtained at anend of every step and the predicted number of finally obtainable normalchips can be calculated at that time point. Therefore, when it isdetermined that the predicted number does not satisfy the requirednumber of chips, the user can correspond thereto by such as the input ofa new lot.

[0315] According to the present production managing system in which theestimated yield is obtained at an end of every step and the predictednumber of finally obtainable normal chips can be calculated at that timepoint, the user can reduce the number of wafers in that lot to a valueenough to obtain the required number of chips at a time when thepredicted number of finally obtainable normal chips substantiallyexceeds the desired number of chips and perform the subsequent steps.Therefore, there is no case where unnecessary chips are produced, sothat the unit cost of chip can be reduced.

[0316] Further, since, in the production managing system ofsemiconductor devices of the present invention, the prearranged date ofcompletion of the semiconductor devices is calculated on the basis ofthe processing schedule table, FIG. 13 and FIG. 14, it becomes easy toplan the production schedule after the semiconductor devices areproduced. Further, since it is possible to set the prearranged date ofcompletion within the range of the schedule table by changing theproduction method by the user, it becomes possible to regulate theproduction cost of the semiconductor devices by regulating theprearranged date of completion correspondingly to an object.

[0317] The production management of semiconductor devices may beperformed by recording a program for realizing all of the steps shown inFIG. 16 to FIG. 18, or any of the steps or any combination thereof in acomputer readable recording medium, reading the program in a computersystem and executing it. Incidentally, in this description, the“computer system” includes a hardware such as OS or peripheralequipment. Further, the “computer readable recording medium” means amobile medium such as floppy disk, opto magnetic disk, ROM, CD-ROM,etc., and a memory such as hard disk housed in a computer system.

[0318] Further, the “computer readable recording medium” may include arecording medium, which holds the program for a constant time, such as acommunication line, which dynamically holds the program for a short timein a case where the program is transmitted through a network such as aninternet or a communication line such as telephone line or a volatilememory in the computer system, which functions as a server or a clientin such case. The above mentioned program may realize a portion of theabove mentioned function or may realize the function by a combination ofit and a program already stored in the computer system.

[0319] In the production managing system of semiconductor devices of thepresent invention, the estimated yield is obtained at the end time ofevery step and the predicted number of normal chips obtainable finallycan be calculated at that time. Therefore, when the predicted number ofnormal chips does not satisfy the required number of chips, the user cantake measures such as a throwing in of a new lot, appropriately.

[0320] Further, according to the production managing system ofsemiconductor devices of the present invention, the estimated yield isobtained at the end time of every step and the predicted number ofnormal chips obtainable finally can be calculated at that time.Therefore, the user can regulate the number of wafers of the current lotcorrespondingly to the number of wafers corresponding to the requirednumber of chips at a time when it is determined that the predictednumber of normal chips substantially exceeds the required number ofchips and can flow the subsequent steps. Consequently, there is no casewhere an excessive number of chips is produced and it is possible toreduce the cost of unit chip.

What is claimed is:
 1. 1.Aproduction managing system for semiconductordevices, comprising a semiconductor device producing center connected toat least one user terminal through an information communication line,said semiconductor device producing center comprising: a plurality ofproduction devices for performing production processes in respectiveprocess steps of semiconductor devices; a corresponding number ofin-line measuring devices provided net to respective said productiondevices, for measuring process parameters corresponding to therespective process steps of said production devices and outputting theprocess parameters measured in units of lot of said semiconductordevices as measured data; a database storing, for each wafer groupincluding one or more wafers, at least data of production methods forproducing said semiconductor devices, the measured data, specificationsof the process steps corresponding to the measured data, estimatedyields, data of the input date and hour of a lot, data of the scheduleddate on which each process step is performed, data of the actual date ofcompletion of every step and data of the scheduled date of completion ofsaid semiconductor devices, correspondingly to lot number data of saidsemiconductor devices; and a server including an estimated yieldoperating unit for calculating the estimated yield, which is a finalyield, on the basis of the specifications and the measured data, and aproduction managing unit for performing a production management ofsemiconductor devices ordered by a user on the basis of the respectivedata inputted by the user and the estimated yields, said serverperforming write and read of the respective data inputted from said userterminal with respect to said database.
 2. A production managing systemof semiconductor devices, as claimed in claim 1, wherein said productionmanaging unit manages the production of semiconductor devices byproducing process control tables for said respective wafer groups, eachof which is composed of the scheduled date and hour data of each of theprocess steps used for a lot management, on the basis of the productionmethod data, the lot input date and hour data and the data of scheduleddate of completion and controlling the process steps of said respectivelots on the basis of said process control tables.
 3. A productionmanaging system of semiconductor devices, as claimed in claim 1, whereinsaid estimated yield operating unit calculates the estimated final yieldon the basis of statistical values of process parameters, thespecifications and old data after the process steps of said lot iscompleted and the process parameters are measured on the basis of thespecifications.
 4. A production managing system of semiconductordevices, as claimed in claim 1, wherein said user terminal outputs thespecifications inputted by the user for respective process steps, themeasuring position data indicative of positions on said wafer to bemeasured and the element data indicative of the kind of measuringelements for performing the measurements to said server together withsaid lot number and said server writes the inputted specifications, themeasuring position data and the element data in a region of saiddatabase corresponding to said semiconductor devices corresponding tothe lot number data.
 5. A production managing system of semiconductordevices, as claimed in claim 1, wherein said user terminal outputs thedata of lot re-input date and the data of wafer numbers of wafers ofsaid re-input lot inputted by said user correspondingly to the estimatedyield to said server and said server writes the scheduled process datafor every process step of said lot correspondingly to the productionschedule based on the data of re-input date and the data of re-inputwafer numbers.
 6. A production managing system of semiconductor devices,as claimed in claim 1, wherein, when the estimated yield estimated bythe measurement result in every step is lower than a minimum yieldassigned by the user, the production managing unit notifies the userterminal of the detection result.
 7. A production managing system ofsemiconductor devices, as claimed in claim 1, wherein said in-linemeasuring devices irradiate through-holes formed in an insulating filmfor electrical connection between wiring patterns laminated on bothsides of the insulating film with electron beam, measure electriccurrent values flowing correspondingly to a configuration of saidthrough-holes and output the measured current values as the measureddata.
 8. A production managing system of semiconductor devices asclaimed in claim 1, wherein said estimated yield operation unitcalculates estimated yield in every step on the basis of old data,calculates the number of normal products of every wafer group on thebasis of the estimated yield and calculates estimated cost of thesemiconductor device on the basis of the number of normal products andthe working ratio of the production device.
 9. A production managingmethod for semiconductor devices, comprising the steps of: inputting atleast data of method for producing semiconductor devices, measured data,specifications of the process step corresponding to the measuring data,data of lot input date and hour, data of scheduled step date, data ofactual date of completion in every step and data of scheduled date ofcompletion of the semiconductor devices, all of which are inputted by auser through a user terminal for every wafer group including at leastone wafer; storing the method data, the measuring data, thespecifications of the step corresponding to the measured data, the dataof lot input date and hour, the data of scheduled process step date, thedata of actual date of completion in every step and the data ofscheduled date of completion of the semiconductor devices in a database;performing process processing corresponding to the process stepssequentially performed in each of a plurality of production devices;measuring process parameters corresponding to process in every of theprocess steps, calculating an estimated yield, which is a final yield,in every wafer group on the basis of the measured parameter data and thespecification in every process step; and storing these data for everywafer group in the database, wherein the production management of thesemiconductor devices ordered by the user is performed on the basis ofthe respective data inputted by the user and the estimated yield.
 10. Aproduction managing program for performing a semiconductor productionmanagement by using the production managing system as claimed in any ofclaims 1 to 8, comprising the steps of: inputting at least the data ofmethod for producing semiconductor devices, the measured data, thespecifications of the process step corresponding to the measured data,the data of lot input date and hour, the data of scheduled process stepdate, the data of actual date of completion in every step and the dataof scheduled date of completion of the semiconductor devices, all ofwhich are inputted by the user through said user terminal for everywafer group including at least one wafer; storing the method data, themeasured data, the specifications of the step corresponding to themeasuring data, the data of lot input date and hour, the data ofscheduled process step date, the data of actual date of completion inevery step and the data of scheduled date of completion of thesemiconductor devices in a database; performing process processingcorresponding to the process step sequentially performed in each of theplurality of said production devices; measuring process parameterscorresponding to the processes in every of the process steps;calculating an estimated yield, which is a final yield, in every wafergroup on the basis of the measured parameter data and the specificationin every step; and storing these data for every wafer group in saiddatabase, wherein the production management of the semiconductor devicesordered by the user is performed by a computer on the basis of therespective data inputted by the user and the estimated yield.